Britain 's Prince Charles has called on governments around the world to do more to ensure religious freedom and urged religious leaders to promote tolerance between people of different faiths .

In a video message recorded to accompany the release of a new report on religious freedom , Charles said current events in Iraq and Syria -- where Sunni extremist group ISIS has been massacring people of other faiths and sectarian tensions have flared -- were `` horrendous and heartbreaking . ''

`` We 've learned with mounting despair of the expulsion of Christians , Muslims and Yazidis from towns and cities that their ancestors have occupied for centuries , '' he said .

`` It is an indescribable tragedy that Christianity is now under such threat in the Middle East , an area where Christians have lived for 2,000 years and across which Islam spread in 700 A.D. , with people of different faiths living together peaceably for centuries . ''

The report , by Roman Catholic charity Aid to the Church in Need , highlights the plight of Christians in particular , saying they `` remain the most persecuted faith in the world . ''

It adds that `` Muslims also face serious persecution ; often from other Muslims who do not share their exact same beliefs , '' while Jews in parts of Western Europe are increasingly feeling threatened , prompting many to move to Israel .

Prince Charles , who is heir to the British throne , pointed out that the issue of religious intolerance also affects some African nations and many countries across Asia .

But some hope can be found in the efforts of certain communities and faith leaders who work to overcome division and hatred , and seek instead to engage in interfaith dialogue , he said .

Faith leaders ' duty

Charles , who referred to his own Christian faith in the video , suggested positive action to help tackle intolerance .

`` First and foremost , rather than remaining silent , faith leaders have -- it seems to me -- a responsibility to ensure that people within their own tradition respect people from other faith traditions , '' he said .

He also called on governments to honor their duty to uphold the freedom of people to practice their faith , including converting to a different religion if they choose .

It 's a principle enshrined in Article 18 of the U.N. Universal Declaration of Human Rights . `` Yet even in the West this right is often challenged sadly -- and in many other countries , an absence of freedom to determine one 's own faith is woven into the laws and customs of the nation , '' he said .

Charles reflected on the case of Mariam Yehya Ibrahim , a Sudanese Christian woman who faced a death sentence this year after refusing to renounce her faith . She was eventually released and , after meeting Pope Francis in Rome , arrived in the United States this summer to start a new life with her husband and children .

And he urged those facing persecution not to give up hope , while remaining strong in their faith .

`` My heart goes out to all those around the world but especially at this time in the East , whether Christian , Muslim , Jewish , Buddhist or Hindu , who are so brutally persecuted solely for the faith they profess , '' he said .

Deteriorating conditions

According to the report , which covers the period from October 2012 to June 2014 , 81 of 196 countries in the world , or 41 % , are identified as places where religious freedom is impaired or is in decline .

Another 35 countries were classified as having some religious freedom issues that are `` of concern , '' but with no deterioration in their status .

Change for the better is noted in only six countries , while conditions have deteriorated in 55 nations , the report 's authors found .

Overall , 20 countries are designated as having a high degree of religious persecution . The persecution is linked to extremist Islam in 14 of those countries , while in the remainder it is linked to an authoritarian regime .

`` In the period under review , global religious freedom entered a period of serious decline , '' the report concludes .

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Prince Charles calls on religious leaders to promote tolerance , understanding

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He calls on governments worldwide to uphold people 's right to freedom of religion

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Charles : `` Indescribable tragedy that Christianity is now under such threat in the Middle East ''

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Report by Roman Catholic charity calls Christians `` the most persecuted faith in the world ''